Carbonylation reactions are known in the art. For instance, in EP-A-0,495,547 several examples are disclosed wherein olefins are converted into (thio)esters, acids, anhydrides, and amides, etc., depending on the nature of the coreactant. Similarly, in WO 94/18154, a process modification is disclosed, based on the presence of an amine, whereby the rate of the carbonylation reaction as described in EP-A-0,495,547 is increased.
Whilst the process disclosed in WO 94/18154 provides the desired product in better yield and with greater selectivity than in EP-A-0,495,547, further improvement remains desirable. Indeed, there still remain instances where reaction is slow to proceed if at all.